As conservationist William K. Reilly takes over as Environmental Protection Agency administrator, the agency is embarking on a new policy that opens the nation's food supplies to a multitude of carcinogenic pesticides. Announced in the waning days of the Reagan Administration, this policy gives the highly politicized EPA broad discretion to allow contamination of food with carcinogenic residues of "negligible risk." The policy has already been exercised in recent EPA decisions allowing continued use on fruits and vegetables of the carcino-genic growth regulator Alar and the fungicide captan.

Before the new EPA policy, carcinogenic pesticides in food were regulated under dual standards of the 1954 Federal Food Drug and Cosmetic Act. Residues on raw agricultural commodities were subject to discretionary tolerances in accordance with commercial benefit considerations of the Federal insecticide Fungicide and Rodenticide Act. But, under a 1958 amendment, the so-called Delaney clause, there was an absolute ban — zero tolerance — on residues in processed foods, regardless of commercial benefits.

The scientific basis for Delaney has been under concerted attack by the agrichemical industry since its enactment it has been repeatedly examined by committees and authorities with expertise in carcinogenesis, which have unequivocally concluded that there is no way of setting safe levels for any carcinogen.

In deliberate violation of that law, EPA has failed to ban residues of most carcinogenic pesticides, particularly those registered before 1978, in processed foods. The agency asserts that the pesticides had not been adequately tested, although their continued use was made conditional on such retesting by 1972 amendments to the pesticide law.

To resolve its dilemma, the EPA adopted the new standard allowing negligible risk tolerances for all carcinogenic pesticides on all foods. The basis for this standard was largely derived from a 1987 report by the National Academy of Sciences, which was funded and dominated by agrichemical and food industry interests to the near exclusion of expertise in cancer prevention.

The new policy trivializes cancer prevention for the sake of a marketplace definition of pesticide benefits. The negligible-risk standard is targeted only at residues of active ingredients of individual pesticides. It does not take into consideration the substantial risks from carcinogenic inert pesticide ingredients, contaminants and impurities that may not have been disclosed. Nor does it consider the cumulative and unpredictable effects of numerous carcinogenic pesticides in the total diet, in drinking water and in the air.

This policy also ignores risks from carcinogenic food additives, coal-tar dye colors, animal-feed additives, including hormones, and food-wrapping chemicals and contaminants, which the FDA allows in food in flagrant contravention of the law.

More fundamentally, the negligible-risk policy is based on quantitative risk assessment, which attempts to estimate cancer risks to humans from animal tests. Quantitative risk assessment is at best a pseudo-science and at worst a smoke screen for the numbers used to prop up politically predetermined decisions, such as EPA's recent downgrading of risk estimates for the herbicide 2,4-D, the termite insecticide chlordane and the contaminant 2,3,7,8-dioxin, the most potent known carcinogen. The results of risk assessment for any carcinogen can vary up to 10 million-fold, depending on which mathematical model is arbitrarily selected for assessment.

Finally, the new standard is a powerful disincentive to reduce the 1-billion-pound annual agricultural pesticide usage, and a disincentive to the development and application of alternative pest management or organic farming methods.

EPA's failure to implement the pesticide food-safety law must be corrected, and the law must not be emasculated, as it would be by the new policy and by past legislation introduced by Rep. Henry A. Waxman (D-Los Angeles) and Sen. Edward M. Kennedy (D-Mass.), now slated for reintroduction in Congress.

Instead, the Delaney law must be strengthened and uniformly applied to all carcinogenic pesticide ingredients in processed foods. Tolerance on raw agricultural commodities must be progressively reduced with a mandated zero goal. Until then, state and local initiatives must be developed to protect consumers, including right-to-know laws on pesticide use and residues, and supermarket residue-testing and certification programs.

The nation is losing the war against cancer, which has reached epidemic proportions, now striking one in three people. Consumers nationwide will expect Congress and the Bush Administration to take early and vigorous action to ensure that we can eat safely while reducing our substantial risks of preventable cancer.